In the case of pulverulent cosmetic products which, in order to be used, have to be converted to a liquid-based, in particular water-based, form, for example, it must be ensured that when converting the pulverulent product into the liquid solvent a risk of creating dust for the user does not, as far as possible, take place. Such a risk of creating dust is particularly undesirable and to be avoided if the pulverulent products are strongly acidic, strongly alkaline or chemically active, such as, for example, bleaching powder.
To avoid dust formation, granulation processes have, inter alia, been proposed, for bleaching powders in particular dedusting with oil components. However, besides impaired miscibility of the powder with the liquid components prior to use, these granulation processes with oxidizable components also harbor potential risks, e.g. with regard to reduced storage stability due to the simultaneous presence of oxidizing and oxidizable components. Sometimes, the formulation of components which may be subject to hydrolysis (or in some cases solvatolysis in polar solvents) in oil-based formulations is also of interest.
It has already been proposed to package bleaching powder in a water-soluble film sachet. The powder is then placed in the film sachet into a liquid solvent, the film sachet gradually dissolves and mixing of the powder with the liquid solvent can take place. In practice, however, the delayed solubility of the film sachet has proven to be disadvantageous, i.e. the preparation time is too long and unacceptable for the user.
An object of the invention is therefore to overcome the disadvantages of the prior art. This object is achieved using a mixing device with the features of the present invention. Through a sealable mixing container with a receiving chamber for the product contained in the film sachet and the liquid solvent and the optional further components, internal inserts for the mechanical destruction of the film sachet being provided in the area of the receiving chamber. Here, the mixing mechanism can be used for all aggregate states of the product, in particular piece-form, gel-like, pasty, pulverulent, liquid or the like.
Using such a mixing device, it is possible, after introducing the components and sealing the mixing container, to mechanically destroy and/or to comminute the film sachet containing the pulverulent product, which leads to accelerated dissolution of the film and to a significantly shortened mixing time of the product with the remaining components. Here, the internal inserts in the receiving chamber of the mixing container can in principle be of varying designs where, in the case of the simplest configurations in terms of construction, it is possible to make the internal inserts effective in a simple manner by the mixing device being shaken by the user, which is in any case sensible and useful for increasing the rate of the mixing operation per se.
In order to make the device easier to handle when opening and closing it, it is advantageously provided that the mixing container has a container opening which is sealable by a removable lid. The components to be mixed can then, after the lid has been removed, simply be introduced into the receiving chamber of the mixing container, then the lid can be put back on again.
It is particularly expedient if the internal inserts are formed as an insert arranged in the area of the container opening. After the mixing operation and opening of the container lid, the insert can then be removed from the area of the container opening and the product obtained after mixing can be removed from the container without problems.
According to a first advantageous configuration, it is envisaged that the insert is designed like a lemon squeezer toward the receiving chamber.
Alternatively, it can also be envisaged that the insert is designed like a sieve plate with tapered pins or spikes pointing into the receiving chamber. Furthermore, it can also be envisaged to equip the insert with knife-like elements pointing inwards. In addition, all of the combinations of the specified inserts or others can be envisaged. The film sachet advantageously consists of polyvinyl alcohol or gelatin, but generally of a solid which is soluble in the added liquid solvent to be mixed.
In an advantageous configuration, it is envisaged that the product is a bleaching powder and the liquid solvent is a hydrogen peroxide solution. The mixing device can then be used to prepare a bleaching composition. The further component here is then advantageously a bleaching cream.
The invention also proposes a mixing set with an above-described device and a product contained in a film sachet soluble in a liquid solvent, optionally a receiving container filled with the liquid solvent, and optionally a receiving container filled with a further component.